As network environments, such as the Internet, have been well-established, a web application has become popular which is operated by utilizing a browser on a web-based network system. In order to realize the web application, functions are required for generating a web page dynamically at a server in response to a request from a client, e.g. a browser, and sending the web page to the client. As general means for that, there is JSP (Java® Server Pages) which utilizes Java® (a trademark of Sun Microsystems, Inc., USA) language to realize the dynamic generation of the web page.
Today, there are a very large variety of types of terminals connectable to the Internet. Therefore, also at the web application, it has been required to execute an appropriate process corresponding to the type of the terminal device which attempts to utilize the web application.
Multi-device Authoring Technology (“MDAT”) of International Business Machines Corporation, USA, enables a web application to communicate with various terminals by using appropriate JSP and actions. (for example, see “Everyplace Toolkit for WebSphere Studio”, http://www-3.ibm.com/software/pervasive/products/mobile_apps/everyplace_toolkit.shtml, searched on Jul. 15, 2003).
MDAT is based on an architecture referred to as JSP Model 2, and provides a web application development technology for various kinds of terminals in accordance with MVC (Model, View, Control) model. A web application based on the MVC model comprises a model for describing a business logic, a view for describing a design of data presentation and user input, and a controller for describing a cooperative control for the request from the client and a business process. For example, a definition in abstract representation is used for a model; JSP for a view; a servlet for a controller.
In order to adapt a web application to the various kinds of terminals, it is necessary to provide a plurality sets of JSP, for example, in a view. In MDAT, a JSP file (a view) is generated automatically by a view specializer, based on the abstract representation referred to as a dialog which is not specialized for any particular terminal device. In this case, a terminal which communicates with the application should be previously designated. The view specializer acquires attributes of the designated terminal (used markup language, screen size, number of displayable colors and the like) from a profile database, and generates an appropriate JSP file.
In this way, the MDAT assumes that types of terminals are known at the time of designing a web application to which the terminals access.
As described above, in order to appropriately execute a process by a web application in accordance with a type of a terminal, it is necessary to provide a view corresponding to the type of the terminal. However, it will incur increase in burden on web application development to generate views corresponding to all of the very large variety of types of the terminals which are potentially connectable to the web application through the Internet.
Since the types of terminals connectable to the Internet have increased day by day, it is difficult to accommodate terminals which are not known when a web application is designed.
As a method for accommodating a request from a new terminal, it may be contemplated to generate, at once, all views necessary for a web application when an application server accepts a first request from the terminal.
However, it requires considerable response time for the first request from the terminal.
Moreover, for some types of terminals, which use only (or may not use more than) a part of functions of the web application, if views corresponding to the whole functions of the web application are created, it becomes wasteful since the views are also created with respect to such functions which are not used, according to the design of the web application.
It should be noted that, of course, the above described problem holds true also in the case of using a method other than the JSP as a method for generating views of web applications.